Not that there was ever any doubt about the British songstress' vocal abilities, but wow, did Jessie J show off her powerhouse voice in the intimate and stripped-down setting. Since the performance was solely made up of Jessie J's mind-blowing voice accompanied by an acoustic guitar, she really had the opportunity to flaunt those killer vocal chops. While she sounds incredible throughout the entire performance, the real treat is around the 2:40 mark, when she takes it to a whole other level.